1. Field of the Invention
The present invention generally relates to the field of prior art encompassing devices for developing intense heat through reactions of incendiary mixtures broadly classified as Thermit. More particularly, the invention relates to such devices as utilized specifically for perforating or cutting metals or other materials.
2. Description of the Prior Art
The use of certain chemical mixtures which are capable of an incendiary reaction to produce intense heat is well known. Such reactions are generally referred to as Thermit in nature and may be exemplified by a mixture of equal molecular parts of iron oxide and aluminum which react exothermically to produce aluminum oxide and pure iron while simultaneously producing a great deal of heat in the process. These reactions have been utilized to advantage in metal treatment processes wherein intense heat is necessary for altering the physical shape of the metal.
For example, the Linzell U.S. Pat. No. 2,424,947 teaches that a Thermit type of chemical mixture essentially comprising a stoichiometric mixture of calcium sulphate and aluminum may be compacted together and ignited to produce sufficient heat for use in welding metal members or melting high melting point metals or refractory materials. The specific incendiary mixture disclosed by the Linzell patent differs somewhat from the traditional Thermit reaction in that molten metal is not produced by virtue of the combustion reaction between the aluminum and calcium sulfate.
In addition to the welding of metal members and the melting of high melting temperature metals, Thermit type reactions have also been employed for the specific task of cutting or perforating metals such as well casings. The Stanton U.S. Pat. No. 2,535,964 is exemplary of this type of application. The Stanton device utilizes a heat resistant plug which has recesses formed therein for receiving the Thermit mixture. The plug is lowered into the well casing and the incendiary mixtures are electrically ignited so that the heat of the reaction serves to perforate the adjacent wall portions of the casing.
Though the prior art does recognize that Thermit type reactions produced from various combinations of incendiary mixtures may be utilized in specific applications of metal treatment, there does not exist a simple and portable Thermit type device for cutting or perforating metals or other materials which can be easily adapted for a variety of environments or applications of use. A device of this nature should advantageously be capable of operating in hostile environments, such as below zero temperatures or under water. Moreover, this device should be capable of efficiently perforating or cutting metals or performing a variety of related functions, such as quickly destroying classified papers or articles for security purposes.